选取鄂尔多斯盆地东南部黄龙县、铜川市金锁关地区延长组长6地层沉积碎屑岩为研究对象,运用LA-ICP-Ms锆石U-Pb同位素年代学方法,探讨黄龙、金锁关地区延长组长6地层的物质来源.结果表明,黄龙和金锁关地区锆石年龄范围为2730.4～213.6Ma.其中,金锁关地区锆石年龄比较复杂,大致可分为5个年龄段:2 300～2 730 Ma,1 600 ～2 100 Ma,800～1 200 Ma,400～ 500 Ma和200～352 Ma,有较明显的5个峰值.黄龙地区锆石年龄分为3组,缺失800 ～1 200 Ma,400～500 Ma两段年龄.这5段年龄分别与太古宙末的古微陆块的拼合以及华北克拉通基本形成期的构造热事件、吕梁运动构造热事件(即华北克拉通的破裂与焊接)、新元古代岩浆热事件、早古生代加里东碰撞造山事件以及晚华力西-印支期构造热事件相对应.将两个地区的锆石年龄与周缘地质体年龄结构进行对比后发现,黄龙地区的沉积碎屑岩来源于华北克拉通南缘的岩浆-变质杂岩,而金锁关地区的碎屑岩不仅有华北克拉通古老地壳的再循环,还有秦岭地区剥蚀物质提供的物源.%With clastic rocks of Late Triassic Yanchang Group Chang 6 in Huanglong and Jinsuoguan District on the southeastern margin of the Ordos Basin in as the study object,using LA-ICP-MS zircon U-Pb isoptope geochronologic method to explore the material source of Yanchang Group Chang 6 layer.The data analysis of samples demonstrates that the age range of zircon mainly is from 2 730.4 Ma to 213.6 Ma in Huanglong and Jinsuoguan district,and it is relatively complex in Jinsuoguan district,which can be divided into five age groups:2300 ～ 2730Ma,1 600 ～ 2 100 Ma,800 ～ 1 200Ma,400 ～ 500 Maand200 ～ 352 Ma,there are five obvious peaks.The zircon age is divided into three groups in Huanglong area,missing 800 ～ 1200 Ma,400 ～ 500 Ma age.These five ages are corresponding to the ancient microstones of the ancient universe.The tectonic heat event of the basic formation of the North China Craton;Lv Liang movement tectonic heat event (North China Craton rupture and welding);Neoproterozoic magma thermal events;Early Paleozoic Caledonian collision orogeny and Late Huaxi-Indosinian tectonic thermal events.Contrasting the age of Zircon and Age Geology of Two Regions,the results show that:the sedimentary clastic rocks are derived from the magmatic-metamorphic complex of the southern margin of the North China Craton in Huanglong,there is not only a recycling of the ancient crust of the North China Craton in Jinsuoguan,but also the source of denudation material in Qinling area.
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